Wireless networks (which are sometimes also referred to as wireless communications networks, wireless telecommunications networks or cellular networks, for example) are radio networks which are usually divided into cells, each served by at least one base station (sometimes also called radio base stations).
Different cells in the mobile network experience various loads, interference, variations in load and variations in the number of mobile terminals, like User Equipments (UEs), being located within the different cells. These variations often result in performance variations in different cells and possibly temporary overloads of the capacity or resources in certain cells during, for example, peak hours. In order to supervise the wireless communication network, different performance management (PM) measurements (are briefly just performance measurements (PM)) are performed on, for example, cell level.
In order to supervise a wireless communications network, the different nodes (which may also be referred to as network elements or network nodes) in the wireless communications network may record events by using counters, and the counter values are reported or sent regularly to an Operation and Maintenance, OAM, system. These different counters may be part of PM measurement data. Some of these counters may be per cell or neighbour cell relation (CR). A CR is related to a relation between two neighbouring cells in the wireless communications network.
In 3rd Generation Partnership Project (3GPP) Technical Specification (TS) 32.401 the overall concept and requirements for PM measurements are described. The PM measurements are used to denote the overall cell level performance, instead of the individual UE level performance as in the case of Minimization of Drive Test (MDT) data. In this context, it is also referred, for instance, to TS 32.425 for E-UTRAN PM measurements and 32.405 for UTRAN PM measurements.
Communication networks are being more densified using many radio access technologies (RAT), many frequencies and a mix of large and (many) small cells in the same places. This densification results in that cells in these networks get very many neighbour cells (NC) on different frequencies and RATs. A cell then has a CR to each of these neighbour cells. Typically, each cell has several neighbour relations to other neighbouring cells. A wireless communication network may comprise a very large amount of cells, each cell having a plurality of CRs, resulting in a vast amount of CRs.
Traditionally PM data, like counters, statistics and/or events, is produced in the network and reported to OAM systems, for example, for every CR. With the said densification, the amount of PM data grows into numbers that are difficult to handle in the network nodes, by the backhaul network and in the OAM systems. A network node holds representations not only of the cells controlled by the node itself but also of external cells, cells that are controlled by other network nodes. Some of these ECs are also NCs. The total amount of external cells (EC) and CRs over the network also becomes a problem for the OAM systems. This may be especially the case for Long Term Evolution (LTE) networks, where every base station, which is usually referred to as eNodeB or eNB in LTE, has its own set of ECs and CRs that is mirrored in the OAM systems.
With many CRs, the total amount of measured PM data can thus be extensive. With the so called Automatic Neighbour Relations (ANR) feature in wireless networks, mobile terminals can uniquely identify neighbours meaning that the CRs are automatically introduced upon discovery. Hence, handling PM (measurement) data is a challenge, both in terms of signalling to the OAM system as well as in database storage in the OAM system.
Current solutions, e.g., as described in WO 2013/010566 A1 and WO2013/066241 A1, aim at reducing the PM data to be handled by the OAM systems by reducing or excluding PM data reporting for selected CRs.